In order to perform failure analysis and ultimately to correct failures in storage devices (disk drives) it may be necessary to determine certain information about the magnetic disk(s) used in the drive. There may be multiple locations where the disks are manufactured. The manufacturing process may change from time to time. There can be many reasons why it might be necessary or useful to know such information as the date that a disk was manufactured, the batch number or even a unique identity of a disk so that information as its origin may be correlated with other information such as failure rates. Since disk drives must generally remained sealed in order to continue to function properly, visible markings on the disks may not be viewable without damaging the drive. The magnetic surfaces of the disks must be extremely smooth with peak-to-valley roughness of the magnetic surfaces of some thin film disks being less than 100 Angstroms. In addition there are tribological constraints on materials and physical structures on the magnetic surfaces. Thus, the extremely fine tolerances and properties required for proper functioning of a magnetic disk render conventional marking schemes impractical.